Modeling Evacuation of a Transport System: Application of a Multimodal Mesoscopic Dynamic Traffic Assignment Model

Abstract

In this paper, the analysis of a transportation system under emergency conditions due to hazardous events is considered. To assess the effects on the analyzed transport network, an extension to a mesoscopic dynamic traffic assignment (DTA) model was developed to determine quantitative indicators for estimating the exposure component of the total risk incurred by the transport networks in an area. In particular, a new version that is able to allow for multimodal networks and to consider network reliability was introduced. To give a practical example of the proposed model, it has been applied to two real networks, studying evacuation in the hypothesis that in the event of a calamity the population in the area follows the instructions proposed by the municipal civil protection plan. The work shows how adequate quantitative methodologies based on a dynamic approach can be a useful tool to support the process of evacuation planning at several scales.

Review of intermodal freight transportation in humanitarian logistics

“…In addition to the studies captured from references lists, our database search using keywords yielded studies by Zhang et al [23], Goel [24], di Gangi [25], Verma et al [26], Abdelgawad and Abdulhai [27], Abdelgawad et al [28] and Miller-Hooks et al [29]. Zhang et al [23] investigated the role of intermodal transportation in humanitarian supply chains mainly through interviews and surveys of relief organizations, non-profit organizations and government agencies.…”

“…Goel [24] studied the visibility of rail and road transportation systems that offer shipment and route choices to adjust transportation plans as situations change when supplies are in transit to minimize the total transportation and stock out costs. Di Gangi [25] developed a dynamic traffic assignment (DTA) model to study demand, supply and loading models in order to determine the quantitative indicators of exposed risk in a multimodal transport network that introduces bimodal arcs in a specified road. To minimize shipment costs and exposure risks, Verma et al [26] used a tabu search algorithm in proposing a bi-objective optimization model for scheduling rail−truck intermodal shipments transporting hazardous materials.…”

An approach to define pedestrian escape routes in evacuation

“…Two different simulations have been conducted. The first simulation, realised applying a Dynamic Traffic Assignment (DTA) mesoscopic model [40][41][42], has been performed, and in this case, for fictitious links a constant speed function was considered whilst for corridors and descending flights relationships between speed and specific flow specified and calibrated in [43] have been considered.…”

An aggregate approach to simulate evacuation of a building

“…Paths were obtained from the school evacuation plan. As regards the cost functions adopted, for fictitious links a constant speed function was considered; for corridors and descending flights relationships between speed and specific flow specified and calibrated in [28] has been considered. Demand values used in the simulation were obtained from school attendance on the experimentation day, and users were located in offices and classrooms following the real distribution.…”